CN115567109A

CN115567109A - ODN network fault positioning method and device

Info

Publication number: CN115567109A
Application number: CN202211162951.XA
Authority: CN
Inventors: 余磊; 张辉; 喻杰奎; 周治柱; 俞诗展; 王文忠
Original assignee: Accelink Technologies Co Ltd
Current assignee: Accelink Technologies Co Ltd
Priority date: 2022-09-23
Filing date: 2022-09-23
Publication date: 2023-01-03

Abstract

The invention relates to an ODN network fault positioning method and device. The method mainly comprises the following steps: performing initial test on the ODN network optical fiber by using OTDR at a local side, setting initial test parameters as default test parameters, and setting an initial test curve as a reference curve; marking initial information of the ODN network optical fiber based on the reference curve, and respectively marking information of a primary optical splitter, a secondary optical splitter and the ONU; performing subsequent test on the ODN network optical fiber by using OTDR (optical time domain reflectometer) at a local side and adopting default test parameters to obtain a latest test curve; positioning the ODN fault position according to the latest test curve, the reference curve and the data marked by the information; and learning and updating a reference curve and information labels after the ODN optical fiber line is changed. The invention can solve the problems that ODN network faults are difficult to be automatically and accurately positioned in batches and difficult to maintain.

Description

ODN network fault positioning method and device

Technical Field

The present invention relates to the field of communications technologies, and in particular, to an ODN network fault location method and apparatus.

Background

An Optical Distribution Network (ODN) is an FTTH (Fiber To The Home) Optical cable Network based on PON (Passive Optical Network) devices. The ODN includes an Optical fiber and a passive Optical splitter or coupler, which functions to provide an Optical transmission path between an OLT (Optical line terminal) and an ONU (Optical Network Unit). The ODN optical distribution network generally adopts a two-stage optical splitting architecture, and the ODN optical fiber can be divided into a trunk optical fiber, a primary branch, and a secondary branch, as shown in fig. 1. At present, ODN network faults are on an increasing trend, and fault detection and positioning technologies are urgently needed to be adopted to effectively monitor the ODN so as to reduce the fault processing difficulty of network maintenance personnel and improve the network maintenance efficiency.

The traditional maintenance mode can detect faults by monitoring the optical power of PON ports and ONU at two sides of the ODN, and the method can identify the occurrence of the faults but cannot locate the specific fault position.

In addition, an OTDR (Optical Time Domain Reflectometer) can be used to perform a reverse test on the ODN Optical fiber link at the ONU side, which can locate the specific position of the fault, but needs manual operation, and can only test one branch at the same Time, and cannot perform batch detection on the whole ODN main Optical fiber and each branch Optical fiber.

At present, a fault detection method for the traditional OTDR in the central test at the local side exists, but most of the methods can only judge the approximate position (fault interval) of the ODN fault and cannot accurately locate the specific position of the fault, and compared with an optical power detection method, the method is not greatly improved, so that the detection means is not popularized and applied in a large scale.

Therefore, a method capable of automatically and accurately positioning ODN network faults in batches is urgently needed, and the problems that the ODN network faults are difficult to position and difficult to maintain are solved. In view of this, how to overcome the defects in the prior art, and solve the problems that the ODN network failure is difficult to be automatically and massively located and difficult to maintain, are the difficult problems to be solved in the technical field.

Disclosure of Invention

Aiming at the defects or the improvement requirements in the prior art: the ODN network fault is difficult to position automatically and in batch, and the maintenance is difficult. The invention provides an ODN network fault positioning method and device, which are used for solving the problems.

The embodiment of the invention adopts the following technical scheme:

in a first aspect, the present invention provides an ODN network fault location method, including:

performing initial test on the ODN network optical fiber by using OTDR at a local side, setting initial test parameters as default test parameters, and setting an initial test curve as a reference curve;

marking initial information of the ODN network optical fiber based on a reference curve, and respectively marking information of a primary optical splitter, a secondary optical splitter and ONU;

performing subsequent testing on the ODN network optical fiber by using OTDR at a local side and adopting default testing parameters to obtain a latest testing curve;

positioning the ODN fault position according to the latest test curve, the reference curve and the data marked by the information;

and learning and updating the reference curve and the information label after the ODN optical fiber line is changed.

Further, when the optical fiber of the ODN network is initially tested by using the OTDR at the local side, the test parameters of the initial test include one or more of a range, a pulse width, a test time, and a refractive index of an optical fiber group; when the initial test curve is set as a reference curve, curve point data of the initial test curve, an OTDR test analysis result and OTDR event analysis information are stored, where the OTDR test analysis result includes one or more of an optical fiber length and attenuation, and the OTDR event analysis information includes one or more of an optical fiber starting point, an optical fiber terminal, a reflection event, a position of a non-reflection event, an attenuation value, and a reflection value.

Further, when the initial information of the ODN network optical fiber is labeled based on the reference curve, the initial information label records one or more of a label name, a label type and a relative distance to a previous-stage label, where the label type includes one or more of a first-stage optical splitter, a second-stage optical splitter, an ONU and a splice box, the relative distance to the previous-stage label is calculated by subtracting a distance from a current node to a starting point of a fiber length identification data table to the starting point of the previous-stage node, and the fiber length identification data table is known data.

Further, the labeling the information of the first-level optical splitter, the information of the second-level optical splitter, and the information of the ONU specifically include:

directly marking the position of the optical fiber terminal of the reference curve as a first-level optical splitter;

finding out a corresponding reflection event in the reference curve according to the fiber length identification data table, and marking the reflection event as a secondary optical splitter connected with the primary optical splitter;

and finding a corresponding reflection event in the reference curve according to the fiber length identification data table, and marking the reflection event as the ONU connected with the secondary optical splitter.

Further, when the ODN fault location is located according to the latest test curve, the reference curve, and the data labeled with the information, if the fiber termination location of the latest test curve is smaller than the fiber termination location of the reference curve, it is determined that the trunk fiber between the OLT and the first-stage optical splitter has a fault, and the fault location is the fiber termination location of the latest test curve.

Further, when the ODN fault position is located according to the latest test curve, the reference curve and the data marked by the information, the marks of the secondary optical splitters are traversed in sequence, if the mark position of a certain secondary optical splitter of the latest test curve has no reflection event, and a reflection event is newly added between the primary optical splitter and the secondary optical splitter, the branch optical fiber fault between the primary optical splitter and the secondary optical splitter is determined, and the fault position is the position of the newly added reflection event.

Further, when the ODN fault position is located according to the latest test curve, the reference curve and the data marked by the information, the ONU marks under the second-level optical splitter are traversed in sequence, if a certain ONU mark position of the latest test curve has no reflection event and a reflection event is newly added between the second-level optical splitter at the upper level and the ONU, the branch optical fiber fault between the second-level optical splitter and the ONU is judged, and the fault position is the position of the newly added reflection event.

Further, when the local side uses OTDR and adopts default test parameters to perform subsequent tests on the ODN network fiber, the subsequent tests include one or more of continuous uninterrupted test, periodic polling test, and automatic test for triggering an alarm at the OLT PON port;

the learning and updating reference curve and information label after the ODN optical fiber line changes specifically comprises the following steps: traversing the information labels and the latest test curve, and if the next-level label is changed from the previous-level label position, updating the relative distance between the next-level label and the previous-level label stored in the next-level label.

Further, the OTDR is a high-precision reflection enhanced OTDR, and the OTDR testing direction is from the local side to the user side.

On the other hand, the invention provides an ODN network fault positioning device, which specifically comprises: the ODN network fault location method comprises at least one processor and a memory, wherein the at least one processor and the memory are connected through a data bus, and the memory stores instructions capable of being executed by the at least one processor, and the instructions are used for completing the ODN network fault location method in the first aspect after being executed by the processor.

Compared with the prior art, the invention has the beneficial effects that: after the initial test and the calibration configuration are finished, the whole ODN network can be actively scanned and detected, faults of an ODN trunk, a primary branch and a secondary branch are accurately identified, and specific fault point positions are positioned, so that the ODN network faults are quickly and accurately positioned, and the problems that the ODN network faults are difficult to automatically position in batches and difficult to maintain are solved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention will be briefly described below. It is obvious that the drawings described below are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

Fig. 1 is a schematic diagram of a two-stage optical splitting architecture of an ODN optical distribution network according to the background art of the present invention;

fig. 2 is a flowchart of an ODN network fault location method according to embodiment 1 of the present invention;

fig. 3 is a diagram showing the representation of the fiber length identification data provided in embodiment 1 of the present invention;

fig. 4 is an expanded flowchart of step 200 provided in embodiment 1 of the present invention;

FIG. 5 is an expanded flowchart of step 400 provided in embodiment 1 of the present invention;

fig. 6 is a schematic diagram of fault location of an ODN network trunk optical fiber according to embodiment 1 of the present invention;

fig. 7 is a schematic diagram of fault location of a primary branch optical fiber of an ODN network according to embodiment 1 of the present invention;

fig. 8 is a schematic diagram of fault location of a secondary branch optical fiber of an ODN network according to embodiment 1 of the present invention;

fig. 9 is a schematic structural diagram of an ODN network fault location device according to embodiment 2 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.

The present invention is a system structure of a specific function system, so the functional logic relationship of each structural module is mainly explained in the specific embodiment, and the specific software and hardware implementation is not limited.

In addition, the technical features related to the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other, and the order of the steps may be changed if they are logical and do not conflict with each other. The invention will be described in detail below with reference to the figures and examples.

Example 1:

as shown in fig. 2, an embodiment of the present invention provides an ODN network fault location method, which includes the following steps.

Step 100: and performing initial test on the ODN network optical fiber by using the OTDR at the local side, setting the initial test parameters as default test parameters, and setting the initial test curve as a reference curve.

Step 200: and carrying out initial information labeling on the ODN network optical fiber based on the reference curve, and respectively labeling the information of the primary optical splitter, the information of the secondary optical splitter and the information of the ONU.

Step 300: and performing subsequent testing on the ODN network optical fiber by using the OTDR at the local side and adopting default testing parameters to obtain a latest testing curve.

Step 400: and positioning the ODN fault position according to the latest test curve, the reference curve and the data marked by the information.

Step 500: and learning and updating the reference curve and the information label after the ODN optical fiber line is changed.

Through the steps, the ODN network fault can be quickly and accurately positioned, and the method is suitable for automatic and batch operation. It should be noted that the step 500 is an update iteration step, that is, the iteration result of the step 500 becomes the input of the

steps

300 and 400 for the subsequent test.

Specifically, for step 100 of the preferred embodiment (performing initial test on the ODN network fiber by using OTDR at the local end, setting the initial test parameter as a default test parameter, and setting the initial test curve as a reference curve), in a preferred embodiment, the OTDR is a high-precision reflection enhanced OTDR, and is optimized by hardware and software algorithms (in the prior art), the maximum sampling precision of the OTDR needs to be less than 0.05m, so that the test precision (centimeter level) is improved, and the reflection event detection capability is enhanced, and in addition, the OTDR test direction is from the local end to the user end. In a preferred embodiment, when the ODN network fiber is initially tested by using OTDR at the local side, the test parameters of the initial test include one or more of range, pulse width, test time, and refractive index of the fiber group; when the initial test curve is set as a reference curve, curve point data of the initial test curve, an OTDR test analysis result and OTDR event analysis information are stored, where the OTDR test analysis result includes one or more of results of fiber length, attenuation, and the like, and the OTDR event analysis information includes one or more of information of a fiber starting point, a fiber terminal, a reflection event, a position of a non-reflection event, an attenuation value, a reflection value, and the like.

For step 200 of this preferred embodiment (marking the initial information of the ODN network optical fiber based on the reference curve, and marking the first-stage splitter, the second-stage splitter, and the ONU information respectively), in a preferred embodiment, when marking the initial information of the ODN network optical fiber based on the reference curve, the initial information is marked and recorded with one or more of the information such as a mark name, a mark type, and a relative distance from the previous-stage mark, where the mark type includes one or more of the types such as the first-stage splitter (first-stage OBD), the second-stage splitter (second-stage OBD), the ONU, and the splice box, the relative distance (meter) from the previous-stage mark is calculated by subtracting the distance from the current node to the starting point from the distance from the previous-stage node to the starting point of the fiber length identification data table, and the fiber length identification data table is known data and is provided by the customer. Then, according to the fiber length identification data table (as an example shown in fig. 3), the corresponding reflection events are found in the reference curve, and are sequentially labeled as the secondary optical splitters connected to the primary optical splitters. And finally, finding out corresponding reflection events in the reference curve according to the fiber length identification data table, and sequentially marking the reflection events as the ONUs connected with the secondary optical splitter. The information marking can simultaneously support automatic marking and manual marking through the fiber length identification data table.

For step 200 of the present preferred embodiment, in a preferred implementation, the step of labeling the first splitter, the second splitter, and the ONU information respectively specifically includes the following steps shown in fig. 4.

Step 201: the fiber termination position of the reference curve is directly labeled as a first-order splitter. In this step, the OTDR analyzes the end position of the trunk section as a fiber termination event.

Step 202: and according to the fiber length identification data table, finding out the reflection event connected with the first-stage optical splitter on the reference curve, and marking the reflection event as a second-stage optical splitter connected with the first-stage optical splitter. In the step, the judgment is carried out according to the condition that the position of the node in the fiber length identification data table is the same as the position of the OTDR curve event, and if the position of a certain secondary optical splitter in the table is matched with the position of the certain event point of the OTDR curve, the event point is marked to the certain secondary optical splitter.

Step 203: and finding out a reflection event connected with the secondary optical splitter on the reference curve according to the fiber length identification data table, and marking the reflection event as the ONU connected with the secondary optical splitter. In the step, the judgment is carried out according to the condition that the position of the node in the fiber length identification data table is the same as the position of an OTDR curve event, the judgment is similar to the judgment of a secondary optical splitter, and if the position of a certain ONU in the table is matched with the position of a certain event point of the OTDR curve, the event point is marked as the ONU. It should be noted that, for the search in step 202 and step 203, the splitter, the ONU type, and the location are known in the fiber length identification data table, and the search is performed according to the location, and the reflection event is not different.

For step 300 of the preferred embodiment (performing subsequent testing on the ODN network fiber by using OTDR at the office end and using default testing parameters to obtain a latest testing curve), in a preferred embodiment, when performing subsequent testing on the ODN network fiber by using OTDR at the office end and using default testing parameters, the subsequent testing includes one or more of continuous uninterrupted testing, periodic polling testing, and OLT PON port alarm triggering automatic testing; the OLT PON interface alarm triggering automatic test includes an OLT device alarm or a PON EMS (PON Element Management System, which is a network Element Management System of a PON access network and implements unified Management of PON network Element devices), and acquires an alarm through a southbound or northbound interface. And the default test parameters used in the subsequent test are the initial test parameters stored after the initial test.

For step 400 of the preferred embodiment (locating the ODN fault location based on the latest test curve, reference curve and annotated data), in a preferred embodiment, several conditions are specifically included as shown in fig. 5. It should be noted that the judgment of the following cases is in a sequential order, that is, the first case is judged first, the second case is judged second, and the third case is judged finally.

Step 401 (first case): and if the optical fiber terminal position of the latest test curve is smaller than the optical fiber terminal position of the reference curve, determining that the main optical fiber between the OLT and the first-level optical splitter has a fault, wherein the fault position is the optical fiber terminal position of the latest test curve. Referring to fig. 6, a schematic diagram of the fault location of the trunk fiber of the ODN network corresponding to this situation is shown. In this case, since the OTDR analyzes the end position of the trunk section as an optical fiber termination event, and if the trunk optical fiber fails (is interrupted), the failure (interruption) position is inevitably in the middle of the line, a new optical fiber termination event analyzed by the OTDR test curve test, that is, the end point of the new optical fiber trunk section, can be directly determined as the failure position.

Step 402 (second case): traversing the labels of the secondary beam splitters in sequence, if a certain secondary beam splitter label position of the latest test curve has no reflection event and a reflection event is newly added between the primary beam splitter and the secondary beam splitter, judging that a branch optical fiber between the primary beam splitter and the secondary beam splitter is in fault, and determining the fault position as the position of the newly added reflection event. Referring to fig. 7, a schematic diagram of fault location of a primary branch optical fiber of an ODN network corresponding to the situation is shown. In this case, a fault of the first-stage branch optical fiber forms a new fault point between the first-stage optical splitter and the second-stage optical splitter, and a new reflection peak is reflected on the OTDR curve between the first-stage optical splitter and the second-stage optical splitter; this point is the end point of rayleigh scattering of the primary branch fiber, causing the reflection peak of the secondary splitter connected to the primary branch fiber to disappear on the OTDR curve.

Step 403 (third case): and traversing ONU labels under the second-level optical splitter in sequence, if a certain ONU label position of the latest test curve has no reflection event and a reflection event is newly added between the second-level optical splitter at the upper level and the ONU, judging that the branch optical fiber between the second-level optical splitter and the ONU has a fault, wherein the fault position is the position of the newly added reflection event. Referring to fig. 8, a schematic diagram of fault location of a secondary branch optical fiber of an ODN network corresponding to the situation is shown. Similar to the above situation, in this case, a failure of the secondary branch optical fiber forms a new failure point between the secondary optical splitter and the ONU, and a new reflection peak is reflected between the secondary optical splitter and the ONU on the OTDR curve; this point is the end point of rayleigh scattering of this secondary branch fiber, causing the reflection peak of the ONU connected to this secondary branch fiber to disappear on the OTDR curve.

For step 500 (learning and updating the reference curve and the information label after the optical fiber line change) of the present preferred embodiment, in a preferred implementation, the method specifically includes: traversing the information labels and the latest test curve, and if the next-level label is changed from the previous-level label position, updating the relative distance from the next-level label to the previous-level label stored in the next-level label, namely the relative position information. In addition, in a preferred embodiment, the reference curve and the information label update support system are automatically triggered, the triggering condition can be automatically judged by the system according to an OLT PON port alarm (OLT equipment alarm or PON EMS alarm, collected through a southbound or northbound interface), and the system automatically triggers one-time update after the PON port alarm disappears; or the alarm duration parameter can be automatically judged, and if the alarm duration exceeds a threshold value, one updating is automatically triggered. In a preferred embodiment, the reference curve and the information annotation update simultaneously support manual triggering of the update by the user. In a preferred embodiment, the alarm duration threshold ranges from 1 to 7 days. For example, the threshold is set to 7 days, if the alarm is not processed after exceeding 7 days, the system judges that the alarm is caused by normal line adjustment, and the system automatically updates the reference curve and the information label and clears the alarm.

In conclusion, the embodiment of the invention realizes the rapid and accurate positioning of the ODN network fault and solves the problems that the ODN network fault is difficult to position automatically and in batches and is difficult to maintain.

Example 2:

on the basis of the ODN network fault location method provided in embodiment 1, the present invention further provides an ODN network fault location device for implementing the method and system, as shown in fig. 9, which is a schematic diagram of a device architecture in an embodiment of the present invention. The ODN network fault location apparatus of the present embodiment includes one or more processors 21 and a memory 22. In fig. 9, one processor 21 is taken as an example.

The processor 21 and the memory 22 may be connected by a bus or other means, and the bus connection is exemplified in fig. 9.

The memory 22 is a non-volatile computer readable storage medium, and can be used for storing non-volatile software programs, non-volatile computer executable programs, and modules, such as the ODN network fault location method in embodiment 1. The processor 21 executes various functional applications and data processing of the ODN network fault location device by running nonvolatile software programs, instructions and modules stored in the memory 22, that is, implements the ODN network fault location method of embodiment 1.

The memory 22 may include high speed random access memory and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid state storage device. In some embodiments, the memory 22 may optionally include memory located remotely from the processor 21, and these remote memories may be connected to the processor 21 via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.

Program instructions/modules are stored in the memory 22 and when executed by the one or more processors 21 perform the ODN network fault location method of embodiment 1 described above, e.g., perform the various steps shown in fig. 2, 4, 5 described above.

Those of ordinary skill in the art will appreciate that all or part of the steps of the various methods of the embodiments may be implemented by associated hardware as instructed by a program, which may be stored on a computer-readable storage medium, which may include: a Read Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, etc.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention. Those not described in detail in this specification are within the skill of the art.

Claims

1. An ODN network fault positioning method is characterized by comprising the following steps:

2. The method according to claim 1, wherein when performing initial test on ODN network optical fibers using OTDR at local side, the test parameters of the initial test include one or more of range, pulse width, test time, and refractive index of optical fiber group; when the initial test curve is set as a reference curve, curve point data of the initial test curve, an OTDR test analysis result and OTDR event analysis information are stored, where the OTDR test analysis result includes one or more of an optical fiber length and attenuation, and the OTDR event analysis information includes one or more of an optical fiber starting point, an optical fiber terminal, a reflection event, a position of a non-reflection event, an attenuation value, and a reflection value.

3. The ODN network fault location method according to claim 2, wherein when the initial information labeling is performed on the ODN network optical fiber based on the reference curve, the initial information labeling records one or more of a labeling name, a labeling type and a relative distance from a previous-stage label, wherein the labeling type comprises one or more of a first-stage optical splitter, a second-stage optical splitter, an ONU and a splice closure, the relative distance from the previous-stage label is calculated by subtracting a distance from a current node to a starting point from a previous-stage node to the starting point from a fiber length identification data table, and the fiber length identification data table is known data.

4. The ODN network fault location method of claim 3, wherein the labeling of the first-level splitter, the second-level splitter, and the ONU information respectively specifically comprises:

according to the fiber length identification data table, finding out a reflection event connected with the first-stage optical splitter on a reference curve, and marking the reflection event as a second-stage optical splitter connected with the first-stage optical splitter;

and according to the fiber length identification data table, finding out a reflection event connected with the secondary optical splitter on the reference curve, and marking the reflection event as the ONU connected with the secondary optical splitter.

5. The ODN network fault location method according to claim 4, wherein when the ODN fault location is located according to the latest test curve, the reference curve and the data labeled with information, if the fiber termination location of the latest test curve is smaller than the fiber termination location of the reference curve, it is determined that the trunk fiber between the OLT and the first-stage optical splitter is faulty, and the fault location is the fiber termination location of the latest test curve.

6. The ODN network fault location method of claim 5, wherein when the ODN fault location is located according to the latest test curve, the reference curve and the data labeled with information, the labels of the secondary optical splitters are traversed in sequence, if there is no reflection event at a labeled location of a certain secondary optical splitter of the latest test curve and a reflection event is added between the primary optical splitter and the secondary optical splitter, it is determined that the branch optical fiber between the primary optical splitter and the secondary optical splitter is in fault, and the fault location is the location of the added reflection event.

7. The ODN network fault location method of claim 6, wherein when the ODN fault location is located according to the latest test curve, the reference curve and the information labeled data, the ONU label under the secondary optical splitters is traversed in sequence, if there is no reflection event at a certain ONU label location of the latest test curve and a reflection event is added between the secondary optical splitter at the previous stage and the ONU, the branch optical fiber fault between the secondary optical splitter and the ONU is determined, and the fault location is the added reflection event location.

8. The ODN network fault location method according to any of claims 1-7, wherein when performing subsequent testing on ODN network fibers using OTDR at the local side and adopting default test parameters, the subsequent testing comprises one or more of continuous uninterrupted testing, periodic polling testing and OLT PON port alarm triggering automatic testing;

the learning and updating reference curve and information label after the ODN optical fiber line changes specifically comprises the following steps: traversing the information labels and the latest test curve, and if the next-level label is changed from the position of the previous-level label, updating the relative distance between the next-level label and the previous-level label stored in the next-level label.

9. The ODN network fault location method of any of claims 1-7, wherein the OTDR is a high precision reflection enhanced OTDR, and the OTDR test direction is from local side to subscriber side.

10. An ODN network fault locating device is characterized in that:

comprising at least one processor and a memory, said at least one processor and memory being connected by a data bus, said memory storing instructions executable by said at least one processor, said instructions upon execution by said processor, for performing the ODN network fault localization method of any one of claims 1-9.